11ta kolokviumska prv semestar so logaritmi

#include <stdio.h>
#include <math.h>
//pravi problem koga second digit==0
int main (){

    int number, copynumber, copynumber2;
    int last_digit, secondtolast_digit;
    int flag;
    while(scanf("%d", &number)){
        if(number<=10){
            continue;
        }
        else{
            int temp=number;
            copynumber=0;
            int coef=1;
            int lastdigittemp, secondtolastdigittemp;

            lastdigittemp=temp%10;
            secondtolastdigittemp=temp%100/10;

            if(lastdigittemp < secondtolastdigittemp){
                flag=2;
            }
            if(lastdigittemp > secondtolastdigittemp){
                flag=1;
            }

            while(temp!=0){

                last_digit=temp%10;
                secondtolast_digit=temp%100/10;

                if(flag==3){
                    copynumber+=temp*coef;
                    coef=coef*100;
                }

                if(flag==2){
                    if(last_digit<5 && secondtolast_digit>=5){
                        copynumber+=(secondtolast_digit*10+last_digit)*coef;
                        coef=coef*100;
                    }
                }
                if(flag==1){
                    if(last_digit>=5 && secondtolast_digit<5){
                        copynumber+=(secondtolast_digit*10+last_digit)*coef;
                        coef=coef*100;
                    }
                }

                temp/=100;
                if( log10( (double)temp ) >=0 && log10( (double)temp ) <= 1  ){
                    flag = 3;
                }
            }

            if(copynumber==number){
                printf("%d\n", copynumber);
            }
        }
    }

    return 0;
}